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<div class="titlepage"><div><div><h4 class="title">
<a name="boost_asio.reference.read.overload1"></a><a class="link" href="overload1.html" title="read (1 of 16 overloads)">read (1 of 16
        overloads)</a>
</h4></div></div></div>
<p>
          Attempt to read a certain amount of data from a stream before returning.
        </p>
<pre class="programlisting">template&lt;
    typename <a class="link" href="../SyncReadStream.html" title="Buffer-oriented synchronous read stream requirements">SyncReadStream</a>,
    typename <a class="link" href="../MutableBufferSequence.html" title="Mutable buffer sequence requirements">MutableBufferSequence</a>&gt;
std::size_t read(
    SyncReadStream &amp; s,
    const MutableBufferSequence &amp; buffers,
    typename constraint&lt; is_mutable_buffer_sequence&lt; MutableBufferSequence &gt;::value &gt;::type  = 0);
</pre>
<p>
          This function is used to read a certain number of bytes of data from a
          stream. The call will block until one of the following conditions is true:
        </p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
              The supplied buffers are full. That is, the bytes transferred is equal
              to the sum of the buffer sizes.
            </li>
<li class="listitem">
              An error occurred.
            </li>
</ul></div>
<p>
          This operation is implemented in terms of zero or more calls to the stream's
          read_some function.
        </p>
<h6>
<a name="boost_asio.reference.read.overload1.h0"></a>
          <span class="phrase"><a name="boost_asio.reference.read.overload1.parameters"></a></span><a class="link" href="overload1.html#boost_asio.reference.read.overload1.parameters">Parameters</a>
        </h6>
<div class="variablelist">
<p class="title"><b></b></p>
<dl class="variablelist">
<dt><span class="term">s</span></dt>
<dd><p>
                The stream from which the data is to be read. The type must support
                the SyncReadStream concept.
              </p></dd>
<dt><span class="term">buffers</span></dt>
<dd><p>
                One or more buffers into which the data will be read. The sum of
                the buffer sizes indicates the maximum number of bytes to read from
                the stream.
              </p></dd>
</dl>
</div>
<h6>
<a name="boost_asio.reference.read.overload1.h1"></a>
          <span class="phrase"><a name="boost_asio.reference.read.overload1.return_value"></a></span><a class="link" href="overload1.html#boost_asio.reference.read.overload1.return_value">Return
          Value</a>
        </h6>
<p>
          The number of bytes transferred.
        </p>
<h6>
<a name="boost_asio.reference.read.overload1.h2"></a>
          <span class="phrase"><a name="boost_asio.reference.read.overload1.exceptions"></a></span><a class="link" href="overload1.html#boost_asio.reference.read.overload1.exceptions">Exceptions</a>
        </h6>
<div class="variablelist">
<p class="title"><b></b></p>
<dl class="variablelist">
<dt><span class="term">boost::system::system_error</span></dt>
<dd><p>
                Thrown on failure.
              </p></dd>
</dl>
</div>
<h6>
<a name="boost_asio.reference.read.overload1.h3"></a>
          <span class="phrase"><a name="boost_asio.reference.read.overload1.example"></a></span><a class="link" href="overload1.html#boost_asio.reference.read.overload1.example">Example</a>
        </h6>
<p>
          To read into a single data buffer use the <a class="link" href="../buffer.html" title="buffer"><code class="computeroutput">buffer</code></a>
          function as follows:
        </p>
<pre class="programlisting">boost::asio::read(s, boost::asio::buffer(data, size));
</pre>
<p>
          See the <a class="link" href="../buffer.html" title="buffer"><code class="computeroutput">buffer</code></a>
          documentation for information on reading into multiple buffers in one go,
          and how to use it with arrays, boost::array or std::vector.
        </p>
<h6>
<a name="boost_asio.reference.read.overload1.h4"></a>
          <span class="phrase"><a name="boost_asio.reference.read.overload1.remarks"></a></span><a class="link" href="overload1.html#boost_asio.reference.read.overload1.remarks">Remarks</a>
        </h6>
<p>
          This overload is equivalent to calling:
        </p>
<pre class="programlisting">boost::asio::read(
    s, buffers,
    boost::asio::transfer_all());
</pre>
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      M. Kohlhoff<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
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